Tilting apparatus



April 28, 191 56. I

K. SCHLESINGER T ILTING APPARATUS Filed July 27, 1933 ETA 06C SUPPLY 2 Sheets-sheet l April 28, 1 936- K. SCHLESINGER 2,039,119

TILTING APPARATUS Filed July 27, 1935 2 Sheets-Sheet 2 Patente Apr. 28, 193%? TEES mane

Application July 27, 1933, Serial No. 682,473 In Germany July 30, 1932 7 Claims.

For the production of recording screens with the asisstance of tilting apparatus a connection system is required, which enables:

(1) The image frequency and the line frequency to be varied continuously and at will independently of each other for the purposeof producing synchronism with the transmitter;

' (2) Adjustment of the size of image without variation of the once adjusted frequencies and without distortion of the tilting potential curves, as desired, and

(3) (For example by the variation of corresponding biases) displacement of the position of the centre point of the image, i. e., of the entire image, in both co-ordinates on the screen of the receiver, for example the Braun tube, without in this connection affecting any of the previously adjusted parameters.

If the apparatus is linked up with the house circuit, it is necessary to accomplish that synchronism is not disturbed even in the case of the greatest fluctuations (120%) which may occur in the house-circuit potential.

The subject matter of the invention is a tilting connection which fulfils in proper fashion all of the requirements referred to. A further particular advantage of the connection system according to the invention resides in the fact that the same enables both the line as well as the image-change tilting device to be fed by one and thesame rectifier.

The tilting device according to the invention is illustrated by wayof example in the draw-=. ings. In this connection Figs. 1-4 show details of the arrangement, whilst in Figs. 5 and 6 there is illustrated the total arrangement.

Fig. 1 shows the part of the arrangement serving for regulation of the size and for adjustment of the middle point of the image component.

It is known that the time-linear tilting curve (saw-tooth curve) employed practically througlrout at the present time for television purposes is composed harmonically of a large number of overtones. It has been found that the potential distribution of the curve thus produced must in elude all of these harmonics in equal fashion, i. e., the same must operate independently'of frequency up to at least the tenth overtone. The problem is of particular importance, as the amplitude of the potentials delivered by the tilting generator is pre-determined by the operation thereof-for example, in the case of the glow lamp connection, the connection system with grid glow lamps with and without hot cathode, and connections with electronic tubes, etc.,and a direct variation of this amplitude at the generator is from a practical standpoint only capable of being performed with great difficulty without simultaneous variation of the frequency.

line i leading to the Braun tube.

According to the invention the regulation of the amplitude takes place withthe assistance of a frequency-independent distribution of the potential, with the use of ohmic resistances.

The tilting condenser l in the manner known per se is connected in parallel with a glow lamp 2 or another discharge element responding to amplitude surge values. The charging takes place through the medium of a charging tube 3 with a potential-independent charging current as constant as possible. According now to the invention, provision is made for the connection together of two potentiometers 4 and 5, of which 4 serves for variation of the form and 5 for variation of the position. The value of 4 should be selected in such fashion that the current traversing 4 is always smaller than approximately 1% of the charging current, so that the form of the tilting curve is not varied. An upper limit for the resistance value of 4 is given by the condition that the same must remain without angle up to the stated high harmonics of the number of image changes. This condition is simple to comply with, exactly in connection with the image change with resistances of the order of 10 ohms. The potentiometer 5 serves simultaneously for earthing purposes and for adjustment of the shifting potential.

As set forth more particularly at a later point, it is preferable to earth this resistance at a fixed point and to select the same with an ohmic value as low as possible, for example in such fashion that the same takes over a current of the order of the charging current.

The connection system according to Fig. 1-if necessary with corresponding variation of the resistance valuesmay naturally also be employed for the line device '(the fundamental oscillation of which is approximately of the order of 2,500 periods). It is however,.particularly convenient, as set forth in Fig. 2, to provide a suppression condenser 6 in front of the sizeadjustment potentiometer 4.

The condenser has fundamentally the object of withholding the plate current passing out of the Braun tube from the charging circuit 3, I. In this manner synchronization troubles, which are frequently caused by the connected Braun tube, particularly when the latter operates with strong currents, are precluded. Naturally these charging troubles, in accordance with the invention, may also be overcome in other fashion, for example by the use of a filter chain, which does not allow passage of the light-control high frequency, and direct current, in the connecting Since in the arrangement according to Figs. 1 and 2 it is fundamentally compulsory to earth a certain middle pole of the operating batteries determined by the centre point of oscillation of the tilting device, it is impossible to earth one of the two feed bar 20 or 2| of the battery 22 (Fig. 3). If, therefore, requirement exists for adjustment of two different earth points in the two components 23 and 24 for the two axes, it is necessary to operate with two different potential sources for the image and line components, as otherwise the potentials of the two lead lines would not agree in relation to earth, and a part of the battery would be short-circuited. According to the invention, the earth point 25 of the image changing device and the earth point 26 of the line changing device-without consideratlon to the particular centre point of oscillation existing with regard to the two components 23 and 24are so adjusted that no further compensating current traverses the connecting line 25, 26. Displacement of the position of the centre point of oscillation on the image screen may then be compensated by means of the potentiometers 5 and Ill. It is desirable to employ tilting relays 2 and II with as far as possible the same electrical data. According to the invention, this is possible-in. particularly ready fashion if in place of cold glow lamps there are employed tilting glow lamps with hot cathodes.

The connection system according to the invention enables the two tilting devices to be fed quite readily from the same current source (for example, from the same rectifier) Since under certain circumstances a mutual effect may be exerted by the line tilting potential and the image tilting potential, tuning-out elements are provided in accordance with the invention, for example in the form of the resistanoes I2, I 3 and the condensers H, l5. Naturally in place of this simple condenser-resistance chain there may be employed any other filter chain which is incapable of being passed by the line frequency and its harmonics, for example a lowpass filter. At the same time the feed of the image-change portion of the system may take place through the medium of filter elements I6,

H, which prevent the passage of all oscillations which are higher, for example, than the imagechange frequency itself.

If necessary, there must also be provided in the common earth line filters, which allow the passage merely of the frequencies of the particular generator connected at the time, and block those to'the side thereof.

It has been found that when employing, for example, good controllable grid glow tubes with hot cathodes, and more particularly when making use of charging through the medium of tubes having a small reciprocal of the amplification factor, fluctuations in the house-circuit potential produce strong effects of flow. Synchronism is de-' stroyed entirely with a fluctuation in potential amounting to 53%. The disturbance is explained according to extent and direction by increase of the charging current of the charging tube 3 in Fig. 4, which arises from the fact that the grid or grids of this three-electrode or fourelectrode tube becomes more positive as com-=- pared with the hot cathode upon an increase in the potential of the network anode 27. Early ignition then takes place at the glow device 2.

This disturbance may be overcome in accordance with the invention by the use of a glow gap divider of the kind known per se in place of the ohmic potential divider 5 otherwise employed.

An additional connection system for eliminating the stated error, in which solely ohmic resistances are employed, is illustrated in Q 'justing potentiometer. the corresponding potentiometers are designated heating line of the feed tubes.

According to the invention, a resistance 30 is connected in the cathode line.

This resistance imparts to the cathode 28 of the charging tube an additional negative bias as compared with its grid, whicltis compensated by displacement of the grid-connection point 29 at the potentiometer 5. The resistance 30, with suitable size, exerts a considerable stabilizing efiect, cause the drop in potential at the same produces a variation of the effective grid bias in 'the charging tube, which acts exactly in opposition to the detrimental influence of the fluctuation in the network. It is possible, for example, with a resistance of 10,000 ohms and a charging current amounting on an average to 5 milliamperes to raise the detrim'ental limit in respect of the fluctuation in the network potential from 13% to i15%. The resistance 30 is preferably not bridged for the tilting frequency produced. The same then causes dynamically an improvement in all errors in form otherwise produced by relaxation of the current of the charging tube.

In Fig. 5 there is shown by way of example the complete arrangement, according to the invention, of a network tilting apparatus operated with central source of current. I and 2 are the two network-heated screening grid charging tubes, 3 and 4 the charging condensers, and 5 and 6 grid glow tubes with hot cathode and fillingof gas. To overcome spark disturbance there are employed filter chain 1, 8 or 9, Ill and also the screening hoods H and I2. The stabilizing and curve-improving resistances are designated l3 and M. The image-tilting device, which is arranged in the screen box operates with a purely galvanic distribution of the potential over the potentiometer l5, the size-adjusting potentiometer, and the potentiometer IS, the position-ad- In the line component I! and I8. 'In addition to these there is the blocking device i9, which has been described with regard to its effect, and which overcomes the disturbing influence of'the connected tube. The single-battery operation is rendered possible by correctly bridge-balanced earthing points 20 or 2| of the potentiometers I6 and I8. Filter chains 22, 23, 24 ensure that the two oscillation components are not superposed. The condenser 25 serves to remove the line curvature. The filterchain member 26 causes analysis of the line or image-changing tone transmitted by the sending station into its two components. The pick-up takes place at the terminals 21 for the vertical co-ordinate and 28 for the horizontal co-ordinate.

The synchronizing impulses arrive at the terminal 29. Central earthing for the entire system is situated at 30. The network anode itself is steadied as well as possible by a large block 3|.

According to the invention, a simplification may be obtained at this point by the use of glow lamp stabilizers.

In Fig. 6 there is illustrated by way of example a form of embodiment of the arrangement according to the invention employing glow gap dividers. In this figure 3| and 32 are two seriesconnected glow-gap dividers, which if necessary may be replaced by one single suitably dimensioned potential divider, and 34 and 35 iron wire hydrogen resistances, which are provided in the As shown by the drawings, the use of a single-way rectifier 33 is quite readily possible in the case of this connection system. The steadying means may be considerably simplified.

The following values may for instance suitably be employed for the arrangement illustrated in Fig. 6.

34:1.0 amp. 4-12 volts 35:1.0 amp. 4-12 volts 36:6000 ohms (wire-resistance) 31:0.310 ohms 38:3000 ohms 39=l0,000 ohms 40:0.310 ohms 4!:03-10 ohms 42:510 ohms 43=100,000 ohms 4 l=25,000 ohms 45:2000 ohms 66:310 ohms d'i=2-10 ohms 48=100,000 ohms 49=10,000 ohms 50:5-10 ohms 52:2-10 ohms 53:3-10 ohms fi=100,000 ohms 55=25,000 ohms 56:1,000 ohms 57:1-10 ohms 6l=0.0001 62:1 63:0.0003 M=4 65:0.0001 66:0.01 61:0.01 68:2 69:0.008 76:0.005 1l=0.02 12:2 13:0.01 7d=2 300 volts :4 volts 16 are the connections for the vertical deflectig plates,

18 are the connections ecting plates,

H are the connections for the synchronizing altage. v

The arrangement as shown otherwise agrees 1 substance with the arrangement according to lg. 5. The single elements may be selected in ie manner shown in the drawings; naturally, iwever, it is also possible to modify the values any of these. As shown by the drawings, the zating of the two tilting tubes should not take ace from the same source, as in this case dis rbing couplings would take place. The arrangement according to the invention akes it possible for the first timeto vary the zqucncy, the form and the position of the age as desired completely independently of each er. For feeding the two tilting devices mereh e single current source is required. The in ence of the network potentials is reduced to a nimum. it is possible with the arrangement according to invention to vary both the width as well as height of the image as desired. It is prefble, however, to maintain the form of image. the ratio between width and height, constant, example equal to the form of the transmitted tge. According, therefore, to the invention,

for the horizontal dethe operating buttons of the two potentiometers determining height and width of the image may be coupled together mechanically in such fashion that the ratio between height and width remains constant in connection with each size of image. Naturally the coupling may be made variable, so that it is possible to adjust any desired form. (By the term form as here employed there is understood the shape and not the dimensional size of the image.)

I claim:

' 1. Means for producing tilting oscillations having a direct and a variable current component comprising a unidirectional source of potential, a condenser, means for charging said condenser from said source, said condenser and said charging means being connected across said Source, means for discharging said condenser, independent means for adjusting said direct and said variable current component, said means for adjusting said direct current component comprising a po tentiometer resistance connected across said source, said means for adjusting said variable current component comprising a second potentiometer resistance, the one end of said second potentiometer resistance being connected to a tap ping point or said first potentiometer resistance and, the other end between said condenser and said charging means, and output connections, one being connected to a second tapping point of said first potentiometer resistance, said second tapping point being connected to an earthed point and the other output connection beting connected to a point on said second potentiometer resistance,

2. Means for producing tilting oscillations having a direct and a variable current component comprising a unidirectional source of potential, a condenser, means for charging said condenser from said source, said condenser and said charging means being connected across said source, means for discharging said condenser, independent means for adjusting said direct and said variable current component, said means for adjusting said direct current component comprising a potentiometer resistance connected across said source, said means for adjusting said vari able current component comprising a second potentiometer resistance and a second condenser in series, the free end of said second potentiometer resistance being connected to a tapping point of said first potentiometer resistance and the free end of said second condenser between said condenser and said charging means, and output connections, one being connected to a second tapping point of said first potentiometer resistance, said second tapping point-being connected to an earthed point and the other output connection being connected to a point on said second potentiometer resistance.

3. Means for producing tilting oscillations having a direct and a variable current component comprising a unidirectional source of potential, a condenser, means for charging said condenser from said source, said. condenser and said charging means being connected across said source, means for discharging said condenser, independent means for adjusting said direct and said variable current component, said means for adjusting said direct current component comprising a potentiometer resistance connected source, said means for adjusting said variable current component comprising a second potentiometer resistance of 10 the charging-circuit and of the first potentiometer across said.

ohms, the impedance of component, said means for adjusting resistance being proportioned to the resistance of the second potentiometer resistance so that the charging current and the current through the first potentiometer resistance are of the same order of magnitude and the current through the secondpotentiometer resistance is less than 1% of the charging current, the one end of said second potentiometer resistance being connected to a tapping point of said first potentiometer resistance and the other end between said condenser and said charging means, and output connections, one being connected to a second tapping point of said first potentiometer resistance, said second tapping point being connected to an earthed point and the other output connection being connected to a point on said second potentiometer resistance. 7

4. In combination two devices for producing tilting oscillations each having a direct and a variable current component, said devices being connecte'd to one unidirectional source of potential, each device comprising a condenser means for charging said condenser from said source, said condenser and said charging means being connected across said source, means for discharging said condenser, independent means for adjusting said direct and said variable current said direct component comprising a potentiometer resistance connected across said source, said means for adjusting said variable current component comprising a second potentiometer resistance, the one end of said second potentiometer resistance being connected to a tapping point of said first potentiometer resistance and the other end between said condenser and said charging means, and output connections, one being connected to a second tapping point of said first potentiometer resistance, said second tapping point being connected to an earthed point and the other output connection being connected to a point on said second potentiometer resistance.

5. In combination two devices for producing tilting osciliations, the one device producing an oscillation of low frequency for image deflection and the second device producing an oscillation of higher frequency for line deflection, each'oscillation having a direct and a variable current component, said devices being connected to one unidirectional source of potential, said device for producing low frequency comprising a condenser and means for charging said condenser and filter elements having a high impedance to said higher frequency connected in series across said source, said device for producing higher frequencies comprising a condenser and means for charging said condenser connected in series across said source and high pass filter means having a cutoff at said low frequency connected between said source and said series combination of condenser and charging means, separate means for discharging each condenser, independent means for adjusting said direct and said variable current cornponcnt of each oscillation wave, said means for adjusting said direct current component comprising a potentiometer resistance across the series combination of the condenser and charging means, said means for adjusting said variable current component comprising a second potentiometer resistance, one end of said second potentiometer-resistance being connected ping point on said first potentiometer resistance and the other and between said condenser and said charging means, and output connections,

to a tapone being connected to a second tapping point of said first potentiometer resistance, said second tapping point being earthed and the other output connection being'connected to a point on said second potentiometer resistance.

6. In combination two devices for producing tilting oscillations each having a direct and a variable current component, said device being connected to one unidirectional source of potential, each device comprising a condenser, means for charging said condenser from said source, said condenser and said charging means being connected across said source, means for discharging said condenser, independent means for adjusting said direct and said variable current component, said means for adjusting said direct current component comprising a potentiometer resistance connected across said series combination of condenser and charging means, said means for adjusting said variable current component comprising a second potentiometer resistance, the one end of said second potentiometer resistance being connected to a tapping point of said first potentiometer resistance and the other end between said condenser and said charging means, and output connections, one being connected to a second tapping point of said first potentiometer resistance, said second tapping point being connected to an earthed point and the other output connection being connected to a point on said second potentiometer resistance, filter means comprising resistances between said source and one series combination of condenser and charging means and condensers between the terminals of said source and said ground.

7. In combination two devices for producing tilting oscillations, the one device producing an oscillation of low frequency for image defiectior and the second device producing an oscillatior of high frequency for line deflection, each oscillation having a direct and a variable curren' component, said devices being connected to on: unidirectional source of potential, said sourcl comprising a glow gap divider connected acros, a common supply network, each device compris ing a condenser, a screening grid tube for charg ing said condenser from said source, a grid con trolled gas filled hot cathode discharge tub for discharging said condenser, the grid of sail discharge tube being connected to a synchroniz ing impulse line, independent means for adjust ing said direct and said variablecurrent com ponent, said means for ad; usting said direct cur rent component, comprising a potentiometer re sist-ance connected. across said source, a connec tion between the control grid of said chargin tube and a point on said potentiometer, 1311 screen grid of said charging tube being cor nected each to tapping points of said potentiorr eter resistance, said means for adjusting sai variable current component comprising a set ond potentiometer resistance, the one end 1 said second potentiometer resistance being co: nected to a further tapping point of said fir potentiometer resistance and the other end b tween said condenser and the anode of sa screen grid tube, and output connections, 01 being connected to a second tapping point said first potentiometer resistance, said secox tapping point being earthed and the other on put connection being connected to a point i said second potentiometer resistance.

KURT SCHLESINGER. 

